1 /* 2 * MXC GPIO support. (c) 2008 Daniel Mack <daniel@caiaq.de> 3 * Copyright 2008 Juergen Beisert, kernel@pengutronix.de 4 * 5 * Based on code from Freescale, 6 * Copyright (C) 2004-2010 Freescale Semiconductor, Inc. All Rights Reserved. 7 * 8 * This program is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU General Public License 10 * as published by the Free Software Foundation; either version 2 11 * of the License, or (at your option) any later version. 12 * This program is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. 20 */ 21 22 #include <linux/err.h> 23 #include <linux/init.h> 24 #include <linux/interrupt.h> 25 #include <linux/io.h> 26 #include <linux/irq.h> 27 #include <linux/irqdomain.h> 28 #include <linux/irqchip/chained_irq.h> 29 #include <linux/gpio.h> 30 #include <linux/platform_device.h> 31 #include <linux/slab.h> 32 #include <linux/basic_mmio_gpio.h> 33 #include <linux/of.h> 34 #include <linux/of_device.h> 35 #include <linux/module.h> 36 #include <asm-generic/bug.h> 37 38 enum mxc_gpio_hwtype { 39 IMX1_GPIO, /* runs on i.mx1 */ 40 IMX21_GPIO, /* runs on i.mx21 and i.mx27 */ 41 IMX31_GPIO, /* runs on i.mx31 */ 42 IMX35_GPIO, /* runs on all other i.mx */ 43 }; 44 45 /* device type dependent stuff */ 46 struct mxc_gpio_hwdata { 47 unsigned dr_reg; 48 unsigned gdir_reg; 49 unsigned psr_reg; 50 unsigned icr1_reg; 51 unsigned icr2_reg; 52 unsigned imr_reg; 53 unsigned isr_reg; 54 int edge_sel_reg; 55 unsigned low_level; 56 unsigned high_level; 57 unsigned rise_edge; 58 unsigned fall_edge; 59 }; 60 61 struct mxc_gpio_port { 62 struct list_head node; 63 void __iomem *base; 64 int irq; 65 int irq_high; 66 struct irq_domain *domain; 67 struct bgpio_chip bgc; 68 u32 both_edges; 69 }; 70 71 static struct mxc_gpio_hwdata imx1_imx21_gpio_hwdata = { 72 .dr_reg = 0x1c, 73 .gdir_reg = 0x00, 74 .psr_reg = 0x24, 75 .icr1_reg = 0x28, 76 .icr2_reg = 0x2c, 77 .imr_reg = 0x30, 78 .isr_reg = 0x34, 79 .edge_sel_reg = -EINVAL, 80 .low_level = 0x03, 81 .high_level = 0x02, 82 .rise_edge = 0x00, 83 .fall_edge = 0x01, 84 }; 85 86 static struct mxc_gpio_hwdata imx31_gpio_hwdata = { 87 .dr_reg = 0x00, 88 .gdir_reg = 0x04, 89 .psr_reg = 0x08, 90 .icr1_reg = 0x0c, 91 .icr2_reg = 0x10, 92 .imr_reg = 0x14, 93 .isr_reg = 0x18, 94 .edge_sel_reg = -EINVAL, 95 .low_level = 0x00, 96 .high_level = 0x01, 97 .rise_edge = 0x02, 98 .fall_edge = 0x03, 99 }; 100 101 static struct mxc_gpio_hwdata imx35_gpio_hwdata = { 102 .dr_reg = 0x00, 103 .gdir_reg = 0x04, 104 .psr_reg = 0x08, 105 .icr1_reg = 0x0c, 106 .icr2_reg = 0x10, 107 .imr_reg = 0x14, 108 .isr_reg = 0x18, 109 .edge_sel_reg = 0x1c, 110 .low_level = 0x00, 111 .high_level = 0x01, 112 .rise_edge = 0x02, 113 .fall_edge = 0x03, 114 }; 115 116 static enum mxc_gpio_hwtype mxc_gpio_hwtype; 117 static struct mxc_gpio_hwdata *mxc_gpio_hwdata; 118 119 #define GPIO_DR (mxc_gpio_hwdata->dr_reg) 120 #define GPIO_GDIR (mxc_gpio_hwdata->gdir_reg) 121 #define GPIO_PSR (mxc_gpio_hwdata->psr_reg) 122 #define GPIO_ICR1 (mxc_gpio_hwdata->icr1_reg) 123 #define GPIO_ICR2 (mxc_gpio_hwdata->icr2_reg) 124 #define GPIO_IMR (mxc_gpio_hwdata->imr_reg) 125 #define GPIO_ISR (mxc_gpio_hwdata->isr_reg) 126 #define GPIO_EDGE_SEL (mxc_gpio_hwdata->edge_sel_reg) 127 128 #define GPIO_INT_LOW_LEV (mxc_gpio_hwdata->low_level) 129 #define GPIO_INT_HIGH_LEV (mxc_gpio_hwdata->high_level) 130 #define GPIO_INT_RISE_EDGE (mxc_gpio_hwdata->rise_edge) 131 #define GPIO_INT_FALL_EDGE (mxc_gpio_hwdata->fall_edge) 132 #define GPIO_INT_BOTH_EDGES 0x4 133 134 static struct platform_device_id mxc_gpio_devtype[] = { 135 { 136 .name = "imx1-gpio", 137 .driver_data = IMX1_GPIO, 138 }, { 139 .name = "imx21-gpio", 140 .driver_data = IMX21_GPIO, 141 }, { 142 .name = "imx31-gpio", 143 .driver_data = IMX31_GPIO, 144 }, { 145 .name = "imx35-gpio", 146 .driver_data = IMX35_GPIO, 147 }, { 148 /* sentinel */ 149 } 150 }; 151 152 static const struct of_device_id mxc_gpio_dt_ids[] = { 153 { .compatible = "fsl,imx1-gpio", .data = &mxc_gpio_devtype[IMX1_GPIO], }, 154 { .compatible = "fsl,imx21-gpio", .data = &mxc_gpio_devtype[IMX21_GPIO], }, 155 { .compatible = "fsl,imx31-gpio", .data = &mxc_gpio_devtype[IMX31_GPIO], }, 156 { .compatible = "fsl,imx35-gpio", .data = &mxc_gpio_devtype[IMX35_GPIO], }, 157 { /* sentinel */ } 158 }; 159 160 /* 161 * MX2 has one interrupt *for all* gpio ports. The list is used 162 * to save the references to all ports, so that mx2_gpio_irq_handler 163 * can walk through all interrupt status registers. 164 */ 165 static LIST_HEAD(mxc_gpio_ports); 166 167 /* Note: This driver assumes 32 GPIOs are handled in one register */ 168 169 static int gpio_set_irq_type(struct irq_data *d, u32 type) 170 { 171 struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); 172 struct mxc_gpio_port *port = gc->private; 173 u32 bit, val; 174 u32 gpio_idx = d->hwirq; 175 u32 gpio = port->bgc.gc.base + gpio_idx; 176 int edge; 177 void __iomem *reg = port->base; 178 179 port->both_edges &= ~(1 << gpio_idx); 180 switch (type) { 181 case IRQ_TYPE_EDGE_RISING: 182 edge = GPIO_INT_RISE_EDGE; 183 break; 184 case IRQ_TYPE_EDGE_FALLING: 185 edge = GPIO_INT_FALL_EDGE; 186 break; 187 case IRQ_TYPE_EDGE_BOTH: 188 if (GPIO_EDGE_SEL >= 0) { 189 edge = GPIO_INT_BOTH_EDGES; 190 } else { 191 val = gpio_get_value(gpio); 192 if (val) { 193 edge = GPIO_INT_LOW_LEV; 194 pr_debug("mxc: set GPIO %d to low trigger\n", gpio); 195 } else { 196 edge = GPIO_INT_HIGH_LEV; 197 pr_debug("mxc: set GPIO %d to high trigger\n", gpio); 198 } 199 port->both_edges |= 1 << gpio_idx; 200 } 201 break; 202 case IRQ_TYPE_LEVEL_LOW: 203 edge = GPIO_INT_LOW_LEV; 204 break; 205 case IRQ_TYPE_LEVEL_HIGH: 206 edge = GPIO_INT_HIGH_LEV; 207 break; 208 default: 209 return -EINVAL; 210 } 211 212 if (GPIO_EDGE_SEL >= 0) { 213 val = readl(port->base + GPIO_EDGE_SEL); 214 if (edge == GPIO_INT_BOTH_EDGES) 215 writel(val | (1 << gpio_idx), 216 port->base + GPIO_EDGE_SEL); 217 else 218 writel(val & ~(1 << gpio_idx), 219 port->base + GPIO_EDGE_SEL); 220 } 221 222 if (edge != GPIO_INT_BOTH_EDGES) { 223 reg += GPIO_ICR1 + ((gpio_idx & 0x10) >> 2); /* lower or upper register */ 224 bit = gpio_idx & 0xf; 225 val = readl(reg) & ~(0x3 << (bit << 1)); 226 writel(val | (edge << (bit << 1)), reg); 227 } 228 229 writel(1 << gpio_idx, port->base + GPIO_ISR); 230 231 return 0; 232 } 233 234 static void mxc_flip_edge(struct mxc_gpio_port *port, u32 gpio) 235 { 236 void __iomem *reg = port->base; 237 u32 bit, val; 238 int edge; 239 240 reg += GPIO_ICR1 + ((gpio & 0x10) >> 2); /* lower or upper register */ 241 bit = gpio & 0xf; 242 val = readl(reg); 243 edge = (val >> (bit << 1)) & 3; 244 val &= ~(0x3 << (bit << 1)); 245 if (edge == GPIO_INT_HIGH_LEV) { 246 edge = GPIO_INT_LOW_LEV; 247 pr_debug("mxc: switch GPIO %d to low trigger\n", gpio); 248 } else if (edge == GPIO_INT_LOW_LEV) { 249 edge = GPIO_INT_HIGH_LEV; 250 pr_debug("mxc: switch GPIO %d to high trigger\n", gpio); 251 } else { 252 pr_err("mxc: invalid configuration for GPIO %d: %x\n", 253 gpio, edge); 254 return; 255 } 256 writel(val | (edge << (bit << 1)), reg); 257 } 258 259 /* handle 32 interrupts in one status register */ 260 static void mxc_gpio_irq_handler(struct mxc_gpio_port *port, u32 irq_stat) 261 { 262 while (irq_stat != 0) { 263 int irqoffset = fls(irq_stat) - 1; 264 265 if (port->both_edges & (1 << irqoffset)) 266 mxc_flip_edge(port, irqoffset); 267 268 generic_handle_irq(irq_find_mapping(port->domain, irqoffset)); 269 270 irq_stat &= ~(1 << irqoffset); 271 } 272 } 273 274 /* MX1 and MX3 has one interrupt *per* gpio port */ 275 static void mx3_gpio_irq_handler(u32 irq, struct irq_desc *desc) 276 { 277 u32 irq_stat; 278 struct mxc_gpio_port *port = irq_get_handler_data(irq); 279 struct irq_chip *chip = irq_get_chip(irq); 280 281 chained_irq_enter(chip, desc); 282 283 irq_stat = readl(port->base + GPIO_ISR) & readl(port->base + GPIO_IMR); 284 285 mxc_gpio_irq_handler(port, irq_stat); 286 287 chained_irq_exit(chip, desc); 288 } 289 290 /* MX2 has one interrupt *for all* gpio ports */ 291 static void mx2_gpio_irq_handler(u32 irq, struct irq_desc *desc) 292 { 293 u32 irq_msk, irq_stat; 294 struct mxc_gpio_port *port; 295 struct irq_chip *chip = irq_get_chip(irq); 296 297 chained_irq_enter(chip, desc); 298 299 /* walk through all interrupt status registers */ 300 list_for_each_entry(port, &mxc_gpio_ports, node) { 301 irq_msk = readl(port->base + GPIO_IMR); 302 if (!irq_msk) 303 continue; 304 305 irq_stat = readl(port->base + GPIO_ISR) & irq_msk; 306 if (irq_stat) 307 mxc_gpio_irq_handler(port, irq_stat); 308 } 309 chained_irq_exit(chip, desc); 310 } 311 312 /* 313 * Set interrupt number "irq" in the GPIO as a wake-up source. 314 * While system is running, all registered GPIO interrupts need to have 315 * wake-up enabled. When system is suspended, only selected GPIO interrupts 316 * need to have wake-up enabled. 317 * @param irq interrupt source number 318 * @param enable enable as wake-up if equal to non-zero 319 * @return This function returns 0 on success. 320 */ 321 static int gpio_set_wake_irq(struct irq_data *d, u32 enable) 322 { 323 struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); 324 struct mxc_gpio_port *port = gc->private; 325 u32 gpio_idx = d->hwirq; 326 327 if (enable) { 328 if (port->irq_high && (gpio_idx >= 16)) 329 enable_irq_wake(port->irq_high); 330 else 331 enable_irq_wake(port->irq); 332 } else { 333 if (port->irq_high && (gpio_idx >= 16)) 334 disable_irq_wake(port->irq_high); 335 else 336 disable_irq_wake(port->irq); 337 } 338 339 return 0; 340 } 341 342 static void __init mxc_gpio_init_gc(struct mxc_gpio_port *port, int irq_base) 343 { 344 struct irq_chip_generic *gc; 345 struct irq_chip_type *ct; 346 347 gc = irq_alloc_generic_chip("gpio-mxc", 1, irq_base, 348 port->base, handle_level_irq); 349 gc->private = port; 350 351 ct = gc->chip_types; 352 ct->chip.irq_ack = irq_gc_ack_set_bit; 353 ct->chip.irq_mask = irq_gc_mask_clr_bit; 354 ct->chip.irq_unmask = irq_gc_mask_set_bit; 355 ct->chip.irq_set_type = gpio_set_irq_type; 356 ct->chip.irq_set_wake = gpio_set_wake_irq; 357 ct->regs.ack = GPIO_ISR; 358 ct->regs.mask = GPIO_IMR; 359 360 irq_setup_generic_chip(gc, IRQ_MSK(32), IRQ_GC_INIT_NESTED_LOCK, 361 IRQ_NOREQUEST, 0); 362 } 363 364 static void mxc_gpio_get_hw(struct platform_device *pdev) 365 { 366 const struct of_device_id *of_id = 367 of_match_device(mxc_gpio_dt_ids, &pdev->dev); 368 enum mxc_gpio_hwtype hwtype; 369 370 if (of_id) 371 pdev->id_entry = of_id->data; 372 hwtype = pdev->id_entry->driver_data; 373 374 if (mxc_gpio_hwtype) { 375 /* 376 * The driver works with a reasonable presupposition, 377 * that is all gpio ports must be the same type when 378 * running on one soc. 379 */ 380 BUG_ON(mxc_gpio_hwtype != hwtype); 381 return; 382 } 383 384 if (hwtype == IMX35_GPIO) 385 mxc_gpio_hwdata = &imx35_gpio_hwdata; 386 else if (hwtype == IMX31_GPIO) 387 mxc_gpio_hwdata = &imx31_gpio_hwdata; 388 else 389 mxc_gpio_hwdata = &imx1_imx21_gpio_hwdata; 390 391 mxc_gpio_hwtype = hwtype; 392 } 393 394 static int mxc_gpio_to_irq(struct gpio_chip *gc, unsigned offset) 395 { 396 struct bgpio_chip *bgc = to_bgpio_chip(gc); 397 struct mxc_gpio_port *port = 398 container_of(bgc, struct mxc_gpio_port, bgc); 399 400 return irq_find_mapping(port->domain, offset); 401 } 402 403 static int mxc_gpio_probe(struct platform_device *pdev) 404 { 405 struct device_node *np = pdev->dev.of_node; 406 struct mxc_gpio_port *port; 407 struct resource *iores; 408 int irq_base; 409 int err; 410 411 mxc_gpio_get_hw(pdev); 412 413 port = devm_kzalloc(&pdev->dev, sizeof(*port), GFP_KERNEL); 414 if (!port) 415 return -ENOMEM; 416 417 iores = platform_get_resource(pdev, IORESOURCE_MEM, 0); 418 port->base = devm_ioremap_resource(&pdev->dev, iores); 419 if (IS_ERR(port->base)) 420 return PTR_ERR(port->base); 421 422 port->irq_high = platform_get_irq(pdev, 1); 423 port->irq = platform_get_irq(pdev, 0); 424 if (port->irq < 0) 425 return port->irq; 426 427 /* disable the interrupt and clear the status */ 428 writel(0, port->base + GPIO_IMR); 429 writel(~0, port->base + GPIO_ISR); 430 431 if (mxc_gpio_hwtype == IMX21_GPIO) { 432 /* 433 * Setup one handler for all GPIO interrupts. Actually setting 434 * the handler is needed only once, but doing it for every port 435 * is more robust and easier. 436 */ 437 irq_set_chained_handler(port->irq, mx2_gpio_irq_handler); 438 } else { 439 /* setup one handler for each entry */ 440 irq_set_chained_handler(port->irq, mx3_gpio_irq_handler); 441 irq_set_handler_data(port->irq, port); 442 if (port->irq_high > 0) { 443 /* setup handler for GPIO 16 to 31 */ 444 irq_set_chained_handler(port->irq_high, 445 mx3_gpio_irq_handler); 446 irq_set_handler_data(port->irq_high, port); 447 } 448 } 449 450 err = bgpio_init(&port->bgc, &pdev->dev, 4, 451 port->base + GPIO_PSR, 452 port->base + GPIO_DR, NULL, 453 port->base + GPIO_GDIR, NULL, 0); 454 if (err) 455 goto out_bgio; 456 457 port->bgc.gc.to_irq = mxc_gpio_to_irq; 458 port->bgc.gc.base = (pdev->id < 0) ? of_alias_get_id(np, "gpio") * 32 : 459 pdev->id * 32; 460 461 err = gpiochip_add(&port->bgc.gc); 462 if (err) 463 goto out_bgpio_remove; 464 465 irq_base = irq_alloc_descs(-1, 0, 32, numa_node_id()); 466 if (irq_base < 0) { 467 err = irq_base; 468 goto out_gpiochip_remove; 469 } 470 471 port->domain = irq_domain_add_legacy(np, 32, irq_base, 0, 472 &irq_domain_simple_ops, NULL); 473 if (!port->domain) { 474 err = -ENODEV; 475 goto out_irqdesc_free; 476 } 477 478 /* gpio-mxc can be a generic irq chip */ 479 mxc_gpio_init_gc(port, irq_base); 480 481 list_add_tail(&port->node, &mxc_gpio_ports); 482 483 return 0; 484 485 out_irqdesc_free: 486 irq_free_descs(irq_base, 32); 487 out_gpiochip_remove: 488 gpiochip_remove(&port->bgc.gc); 489 out_bgpio_remove: 490 bgpio_remove(&port->bgc); 491 out_bgio: 492 dev_info(&pdev->dev, "%s failed with errno %d\n", __func__, err); 493 return err; 494 } 495 496 static struct platform_driver mxc_gpio_driver = { 497 .driver = { 498 .name = "gpio-mxc", 499 .owner = THIS_MODULE, 500 .of_match_table = mxc_gpio_dt_ids, 501 }, 502 .probe = mxc_gpio_probe, 503 .id_table = mxc_gpio_devtype, 504 }; 505 506 static int __init gpio_mxc_init(void) 507 { 508 return platform_driver_register(&mxc_gpio_driver); 509 } 510 postcore_initcall(gpio_mxc_init); 511 512 MODULE_AUTHOR("Freescale Semiconductor, " 513 "Daniel Mack <danielncaiaq.de>, " 514 "Juergen Beisert <kernel@pengutronix.de>"); 515 MODULE_DESCRIPTION("Freescale MXC GPIO"); 516 MODULE_LICENSE("GPL"); 517